KR20240106598A - Apparatus and method for transmitting Ethernet frame - Google Patents

Abstract

A gateway device according to an embodiment includes an input unit configured to receive an Ethernet frame, a control unit configured to control a transmission order of the data based on priority information about data included in the Ethernet frame, and the transmission An output unit configured to output a first transmission frame based on an order, wherein the control unit transmits the first transmission frame in the current transmission cycle and determines that the time required for transmission of the second transmission frame is shorter than the remaining transmission time. In this case, the second transmission frame is controlled to be transmitted within the current transmission period, and if the time required for transmission of the second transmission frame is longer than the remaining transmission time, the priority of the data in the second transmission frame is adjusted. Based on this, it is possible to determine whether to preempt the second transmission frame.

Description

Ethernet frame transmission device and method {Apparatus and method for transmitting Ethernet frame}

The present invention relates to an apparatus and method for transmitting an Ethernet frame, and more specifically, to an apparatus and method that can reduce the number of frame preemptions when transmitting an Ethernet frame.

As program-based control methods using ECUs (Electronic Control Units) are applied to recent vehicles, their reliability and performance are improving, but the structure of vehicle networks is becoming increasingly complex. Recently, central gateway-type networks are being used in vehicles, and are in the process of changing from a domain-based network structure to a zone-based network structure.

The IEEE 802.1 group announced the Time-Sensitive Networking (TSN) protocol in line with changing vehicle network systems. TSN uses the IEEE 802.1Qav, IEEE 802.1Qbv, and IEEE 802.1Qbu protocols to achieve limited (low) latency. Among these, in order to use the IEEE 802.1 Qav protocol, it is essential to estimate the guard band. If the frame length is long or the transmission time is insufficient, the frame may exceed the guard band and invade the scheduled traffic area where control data is transmitted.

When the Time-Aware Shaper (TAS) algorithm is used to ensure periodicity, no loss, and no delay of control data, a guard band is inevitably used. The guard band refers to a time region (unused time region) in which no information is transmitted to distinguish frames. However, when data such as video, audio, text, etc. are transmitted using the CBS (Credit-Based Shaper) algorithm, if the frame length is long and transmission begins close to the end of the frame transmission cycle, the transmitted frame is not in the guard band. It may go beyond and invade the control data area of the next transmission cycle. Control data consists of data that is sensitive to loss or delay, so situations like this must be prevented. However, if the guard band is expanded to prevent a frame from exceeding the guard band and invading the control data area, unnecessarily waiting time when transmitting a frame becomes longer, reducing the utilization rate of the network system. In order to minimize the guard band, it is efficient to use the frame preemption function, but when the frame preemption function is used, additional processing time is consumed to split or reassemble one frame. Additionally, overhead occurs because a frame header is added to reassemble the divided frames. Therefore, in order to increase network efficiency, a method is required to minimize the unused area in the guard band and reduce the number of frame preemptions.

Republic of Korea Patent Publication No. 10-2021-0122289, published on October 8, 2021.

The technical object of the present invention is to provide an Ethernet frame transmission device and method that can improve network transmission efficiency.

Another technical object of the present invention is to provide an Ethernet frame transmission device and method that can minimize the number of frame preemptions when transmitting an Ethernet frame.

Another technical problem of the present invention is to provide an Ethernet frame transmission device and method that can minimize the unused area in the guard band.

The problems to be solved by the present invention are not limited to those mentioned above, and other problems to be solved that are not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the following description.

According to one embodiment of the present invention, the gateway device includes an input unit configured to receive an Ethernet frame, and a control unit configured to control the transmission order of the data based on priority information about the data included in the Ethernet frame. , and an output unit configured to output a first transmission frame based on the transmission order, wherein the control unit transmits the first transmission frame in the current transmission cycle and transmits the second transmission frame more than the remaining transmission time. If the required time is short, the second transmission frame is controlled to be transmitted within the current transmission period, and if the time required for transmission of the second transmission frame is longer than the remaining transmission time, the data in the second transmission frame is controlled. Based on the priority, it is possible to determine whether to preempt the second transmission frame.

Here, when the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of data in the second transmission frame is greater than the set value, the control unit performs the preemption for the second transmission frame. It can be done.

In addition, if the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of the data in the second transmission frame is less than the set value, the priority of the data in the third transmission frame is set to Based on the fact that it is less than the set value and the size of the data in the third transmission frame is less than the first threshold, the third transmission frame can be controlled to be transmitted preferentially over the second transmission frame.

Here, the first threshold may be set based on the average value of the data size in which the preemption occurs.

Additionally, the priority of data in the second transmission frame and the priority of data in the third transmission frame may be the same.

In addition, if the time required for transmission of the third transmission frame is shorter than the remaining transmission time, the control unit controls the third transmission frame to be transmitted within the current transmission period, and controls the transmission of the third transmission frame. If the required time is longer than the remaining transmission time, it is possible to determine whether to preempt the third transmission frame by comparing the size of data in the third transmission frame with a second threshold.

Here, the second threshold may be set to at least 120 bytes.

In addition, the control unit performs the preemption on the third transmission frame based on that the size of the data in the third transmission frame is greater than or equal to the second threshold, and the control unit performs the preemption on the third transmission frame, and Based on being less than the 2 threshold, the third transmission frame can be controlled to be transmitted in a transmission cycle after the current transmission cycle.

According to another embodiment of the present invention, a transmission method by a gateway device includes receiving an Ethernet frame, controlling a transmission order of the data based on priority information about data included in the Ethernet frame, and Outputting a first transmission frame based on a transmission order, wherein when the time required for transmission of the second transmission frame is shorter than the remaining transmission time remaining after transmitting the first transmission frame in the current transmission cycle, 2 The transmission frame is transmitted within the current transmission period, and if the time required for transmission of the second transmission frame is longer than the remaining transmission time, the second transmission is performed based on the priority of the data in the second transmission frame. Whether or not to preempt a frame may be determined.

According to another embodiment of the present invention, the gateway device has an input unit configured to receive an Ethernet frame, and stores the data among a plurality of buffers based on at least one of priority information and length information for data included in the Ethernet frame. A control unit configured to store data in a corresponding buffer and control the transmission order of the data in the plurality of buffers, and an output unit configured to output a first transmission frame based on the transmission order, wherein the control unit provides a current transmission period. If the time required to transmit the second transmission frame including data stored in the first buffer among the plurality of buffers is shorter than the remaining transmission time remaining after transmitting the first transmission frame, the second transmission frame is transmitted in the current Control to transmit within a transmission period, and when the time required for transmission of the second transmission frame is longer than the remaining transmission time, the second transmission frame is transmitted based on the size of data in the second buffer among the plurality of buffers. You can decide whether or not to preempt.

According to another embodiment of the present invention, a transmission method by a gateway device includes receiving an Ethernet frame, and storing the data in a corresponding buffer among a plurality of buffers based on priority information about data included in the Ethernet frame. Storing, controlling the transmission order of the data in the plurality of buffers, and outputting the first transmission frame based on the transmission order, wherein the first transmission frame is transmitted in the current transmission cycle and the remaining If the time required for transmission of the second transmission frame including data stored in the first buffer among the plurality of buffers is shorter than the remaining transmission time, the second transmission frame is transmitted within the current transmission period, and the second transmission frame is transmitted within the current transmission period, and the second transmission frame is transmitted within the current transmission period. If the time required to transmit a transmission frame is longer than the remaining transmission time, whether to preempt the second transmission frame may be determined based on the size of data in a second buffer among the plurality of buffers.

According to another embodiment of the present invention, a computer program stored in a computer-readable recording medium, when executed by a processor, includes the steps of receiving an Ethernet frame and based on priority information about data included in the Ethernet frame. Controlling the transmission order of the data and outputting a first transmission frame based on the transmission order. Includes instructions for causing the processor to perform a transmission method, wherein the first transmission frame is transmitted in the current transmission cycle. If the time required for transmission of the second transmission frame is shorter than the remaining transmission time remaining after transmitting the frame, the second transmission frame is transmitted within the current transmission period, and the time required for transmission of the second transmission frame is If it is longer than the remaining transmission time, whether to preempt the second transmission frame may be determined based on the priority of data in the second transmission frame.

According to another embodiment of the present invention, a computer-readable recording medium storing a computer program, when executed by a processor, includes the steps of receiving an Ethernet frame and priority information about data included in the Ethernet frame. Controlling the transmission order of the data based on the transmission order, and outputting a first transmission frame based on the transmission order, comprising instructions for causing the processor to perform a transmission method, wherein the first transmission frame is transmitted in the current transmission cycle. If the time required for transmission of the second transmission frame is shorter than the remaining transmission time remaining after transmitting the transmission frame, the second transmission frame is transmitted within the current transmission period, and the time required for transmission of the second transmission frame is If it is longer than the remaining transmission time, whether to preempt the second transmission frame may be determined based on the priority of data in the second transmission frame.

According to an embodiment of the present invention, when transmitting an Ethernet frame, the number of frame preemptions is minimized, thereby reducing overhead and improving transmission efficiency.

According to one embodiment of the present invention, the load on the processor within the gateway device can be reduced because the number of times the gateway device performs frame preemption is reduced.

According to one embodiment of the present invention, the transmission delay of the frame can be reduced because the unused area in the guard band is minimized.

1 is a diagram showing a gateway device according to an embodiment of the present invention.
Figure 2 is a diagram showing the structure of an Ethernet frame used in a gateway device according to an embodiment of the present invention.
Figure 3 is a diagram showing the structure of a fragment frame generated when a gateway device performs frame preemption according to an embodiment of the present invention.
Figures 4 to 8 are diagrams for explaining a process by which a gateway device determines a frame transmission order according to an embodiment of the present invention.
Figure 9 is a diagram showing a method of transmitting a frame by a gateway device according to an embodiment of the present invention.
Figure 10 is a diagram showing a process in which a gateway device receives data according to an embodiment of the present invention.
Figure 11 is a diagram showing a process in which a gateway device stores data according to an embodiment of the present invention.
Figures 12 and 13 are diagrams showing a process in which a gateway device processes data according to an embodiment of the present invention.

The advantages and features of the present invention and methods for achieving them will become clear with reference to the embodiments described below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are merely provided to ensure that the disclosure of the present invention is complete and to be understood by those skilled in the art in the technical field to which the present invention pertains. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

The terms used in this document will be briefly explained, and the present invention will be described in detail.

The terms used in the present invention are general terms that are currently widely used as much as possible while considering the functions in the present invention, but this may vary depending on the intention or precedent of a person working in the art, the emergence of new technology, etc. In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the relevant invention. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall content of the present invention, rather than simply the name of the term.

Throughout this document, when a part ‘includes’ a certain component, this does not mean excluding other components, but may include other components, unless specifically stated to the contrary.

Additionally, the term ‘part’ used in this document refers to software or hardware components such as FPGA or ASIC, and the ‘part’ performs certain roles. However, ‘wealth’ is not limited to software or hardware. The 'part' may be configured to reside on an addressable storage medium and may be configured to reproduce on one or more processors. Therefore, as an example, 'part' refers to components such as software components, object-oriented software components, class components and task components, processes, functions, properties, procedures, Includes subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within components and parts can be combined into a smaller number of components and parts or further separated into additional components and parts.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. In order to clearly explain the present invention in the drawings, parts unrelated to the description are omitted.

1 is a diagram showing a gateway device according to an embodiment of the present invention.

Referring to FIG. 1, the gateway device 100 includes an input unit 110, a control unit 120, and an output unit 130. In Figure 1, as an example, a case where the gateway device 110 receives an Ethernet frame from the first ECU 210 and the second ECU 220 and outputs it to the third ECU 230 is shown, but the gateway device ( 100) can receive Ethernet frames from a plurality of devices in the network and transmit the data in each Ethernet frame to the corresponding device.

The input unit 110 may be configured to receive Ethernet frames from the first ECU 210 and the second ECU 220 included in the Ethernet, respectively. In this case, the input unit 110 includes a first input module configured to receive an Ethernet frame received from the first ECU 210 and a second input module configured to receive an Ethernet frame received from the second ECU 220. can do. The input unit 110 may store data in an Ethernet frame received from the first ECU 210 and the second ECU 220 in an input buffer. Here, the buffer may include a queue. If the input buffer is implemented as a queue, it may be called an input queue.

The control unit 120 may be configured to control the transmission order of data included in the Ethernet frame input to the input unit 110 based on priority information about the data. As an example, the control unit 120 may determine the remaining transmission time of the current transmission cycle after transmission of the first transmission frame in the current transmission cycle is completed. If the time required for transmission of the second transmission frame is shorter than the remaining transmission time, the control unit 120 controls the second transmission frame to be transmitted within the current transmission period, and controls the time required for transmission of the second transmission frame If it is longer than the remaining transmission time, the control unit 120 may determine whether to preempt the second transmission frame based on the priority of data in the second transmission frame.

As an embodiment, the control unit 120 controls the second transmission frame when the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of data in the second transmission frame is greater than a preset value. Preemption can be performed for .

If the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of data in the second transmission frame is less than the set value, the control unit 120 transmits a third transmission frame rather than the second transmission frame. This can be controlled to be transmitted preferentially. In this case, the priority of the data in the third transmission frame may be less than the set value and the size of the data in the third transmission frame may be less than the first threshold. Here, the first threshold may be set based on the average value of the data size at which preemption occurs. And the priority of the data in the second transmission frame and the priority of the data in the third transmission frame may be the same.

Meanwhile, if the time required for transmission of the third transmission frame is shorter than the remaining transmission time of the current transmission cycle, the control unit 120 controls the third transmission frame to be transmitted within the current transmission cycle, and the third transmission frame is transmitted within the current transmission cycle. If the time required for transmission of a transmission frame is longer than the remaining transmission time, the size of the data in the third transmission frame is compared with a second threshold (for example, the minimum transmission possible size) to determine the third transmission frame. You can decide whether or not to preempt. Here, the second threshold may be set to at least 120 bytes. The control unit 120 performs preemption on the third transmission frame when the size of the data in the third transmission frame is greater than or equal to the second threshold, and the size of the data in the third transmission frame is greater than or equal to the second threshold. If it is less than that, the third transmission frame can be controlled to be transmitted in the next transmission cycle of the current transmission cycle or in the transmission cycle after the current transmission cycle.

The output unit 130 may output a transmission frame based on the transmission order determined by the control unit 120. As an example, the output unit 130 monitors the number of data stored in the output buffer, and when input of data is confirmed, it can configure a frame with data in the output buffer and output it to an Ethernet port.

Figure 2 is a diagram showing the structure of an Ethernet frame used in a gateway device according to an embodiment of the present invention.

Referring to FIG. 2, the Ethernet frame includes a preamble field, Start of Frame Delimiter (SFD) field, Des MAC field, Src MAC field, 802.1Q header field, and length/type field. , data field, and CRC (Cyclic Redundancy Check) field.

The preamble field is used for synchronization between the transmitting device and the receiving device and consists of 7 bytes. The preamble field has a fixed value and can include 7 bit strings consisting of ‘10101010’.

The SFD field notifies the start of an Ethernet frame and consists of 1 byte. The SFD field has a fixed value and can be set to ‘10101011’.

The Des MAC field contains the MAC address of the destination and consists of 6 bytes.

The Src MAC field contains the MAC address of the source and consists of 6 bytes.

The 802.1Q header field is used to transfer VLAN ID information between switches on a VLAN (Virtual Local Area Network) and consists of 4 bytes. The 802.1Q header field may be called an 802.1Q tag. The 802.1Q header field includes a 2-byte Tag Protocol IDentifier (TPID) field and a 2-byte Tag Control Information (TCI) field. The TCI field includes a 3-bit PCP (Priority Code Point) field, a 1-bit CFI (Canonical Format Indicator) field, and a 12-bit VID (VLAN ID) field. The PCP field contains information about the priority of data in the data field, and is expressed as a value between 0 and 7. Here, higher numbers indicate higher priority. For example, if the value of the PCP field is 7, this may indicate that the data is network control data, and if the value of the PCP field is 6, this may indicate that the data is internetwork control data. Additionally, if the value of the PCP field is 5, this may indicate that the data is audio data, and if the value of the PCP field is 4, this may indicate that the data is video data. The default value of the PCP field may be set to 0, which may indicate that the data is text data.

The length/type field indicates the network protocol type and the length (number of bytes) of the data field and consists of 2 bytes.

The data field contains a minimum of 42 bytes and a maximum of 1500 bytes of data if an 802.1Q tag is present. Data fields may be called payload.

The CRC field is used to detect frame errors and consists of 4 bytes. The CRC field may be called a Frame Check Sequence (FCS) field.

Figure 3 is a diagram showing the structure of a fragment frame generated when a gateway device performs frame preemption according to an embodiment of the present invention.

When frame preemption is performed, the Ethernet frame may be divided into a plurality of fragments as shown in FIG. 3.

The first fragment frame refers to the first fragment when the frame is divided through frame preemption, and to indicate this, the SFD field is changed to the SMD-Sx (Start Mpacket Delimiter-Start fragment) field. And, the CRC field is changed to an mCRC field indicating that preemption has been applied to the frame.

For the second to last fragment frames, 1 byte is reduced in the preamble field, and a 1-byte Frag Cnt field is added.

The SMD-Cx (SMD-Continue fragment) field indicates the middle fragment of a divided frame, and the fragment number is indicated through the Frag Cnt field.

In the case of the second to last fragment frames, header information has already been transmitted through the first fragment frame, so they do not include header information. That is, the second to last fragment frames do not include the Des MAC field, Src MAC field, 802.1Q header field, and length/type field.

For the last fragment frame, it contains the CRC value of the original frame (frame before splitting). The receiving device can know that the fragment is the last fragment based on the CRC field.

The data field of each fragment frame can contain a minimum of 60 bytes and a maximum of 1500 bytes of data.

Figures 4 to 8 are diagrams for explaining a process by which a gateway device determines a frame transmission order according to an embodiment of the present invention.

Hereinafter, a process by which a gateway device determines a data transmission order will be described as an example with reference to FIGS. 4 to 8 .

The gateway device may determine the transmission order of each data based on at least one of the priority and size (or length) of each data and transmit a frame containing the corresponding data according to the transmission order. To this end, when receiving an Ethernet frame, the gateway device can determine the priority of the data based on priority information in the 802.1Q header field of the Ethernet frame, and determine the size of the data based on the length information in the length/type field. (or length) can be judged. The gateway device can calculate the time required to transmit a frame containing the corresponding data based on the length information.

First, referring to FIG. 4, each transmission cycle includes a transmission section and a guard band. Each transmission section can be divided into a scheduled traffic area (or section) and an unscheduled traffic area (general traffic area). The scheduled traffic area may be located at the front of the transmission section. In the scheduled traffic area, data to be transmitted periodically, such as control data, and/or data sensitive to delay may be transmitted. The general traffic area may be located after the scheduled traffic area in the transmission section. In the general traffic area, data that is relatively insensitive to delay, such as video data, audio data, text data, etc., may be transmitted. The guard band is an area for distinguishing between frames and/or preventing interference, and generally no data is transmitted.

As an example, as shown in FIG. 4, when the gateway device wants to transmit a second transmission frame after transmitting the first transmission frame in the current transmission cycle, the gateway device transmits the first transmission frame and transmits the remaining transmission time. It can be determined whether the second transmission frame can be transmitted. Here, the priority of the data in the first transmission frame may be greater than or equal to the priority of the data in the second transmission frame. At this time, if the size of the second transmission frame cannot be transmitted within the transmission section of the current transmission cycle, but is a size that can be transmitted within the remaining transmission time including the guard band, the gateway device uses the guard band to transmit the second transmission frame. Frames can be transmitted within the current transmission cycle. To this end, the gateway device may transmit the first transmission frame in the current transmission cycle and compare the remaining transmission time remaining with the time required for transmission of the second transmission frame. For example, if you want to transmit an Ethernet frame containing data of 100 bytes in size, the size of the remaining fields except the data field is fixed to 30 (7+1+6+6+4+2+4) bytes. Therefore, it can be seen that the gateway device requires 130 bytes to construct a frame containing the corresponding data. Therefore, the gateway device can determine whether the frame can be transmitted in the current transmission cycle by calculating the time required to transmit a frame with a size of 130 bytes and comparing this with the remaining transmission time including the guard band. At this time, an interpacket gap of 12 bytes may be additionally considered. In this case, when determining whether 100 bytes of data can be transmitted in the remaining transmission time, the gateway device may determine whether the remaining transmission time is enough to transmit 142 bytes.

Meanwhile, as shown in FIG. 5, when the time required for transmission of the second transmission frame is longer than the remaining transmission time including the guard band, the gateway device transmits the second transmission frame based on the priority of the data in the second transmission frame. It is possible to determine whether to preempt a transmission frame. For example, if the time required to transmit the second transmission frame is longer than the remaining transmission time and the priority of the data in the second transmission frame is higher than the set value, the gateway device performs preemption on the second transmission frame. can do. That is, the gateway device can divide the data into a plurality of pieces to form a plurality of fragment frames. In this case, the data may be data that is more sensitive to time delay than general data (e.g., audio data, video data, etc.), and for example, the priority of the data may be 2 or higher. That is, the priority of the data may be 2 to 7.

However, as shown in FIG. 6, if the time required for transmission of the second transmission frame is longer than the remaining transmission time including the guard band and the priority of the data in the second transmission frame is less than the above set value, the gateway device Can control the third transmission frame to be transmitted preferentially over the second transmission frame. That is, the gateway device may transmit the third transmission frame in the remaining transmission time of the first transmission cycle, and then transmit the second transmission frame in the transmission section of the second transmission cycle. In this case, the priority of the data in the third transmission frame may be less than the set value and the size of the data in the third transmission frame may be less than the first threshold. Here, the first threshold may be set based on the average value of the data size at which preemption occurs. Data whose priority is less than the set value and whose size is less than the first threshold may be stored in a separate short buffer, and data in the short buffer whose priority is less than the set value may be stored in the current transmission cycle. In cases where data cannot be transmitted in the remaining transmission time, it may be transmitted with priority over the corresponding data. In the example of FIG. 6, the priority of data in the second transmission frame and the priority of data in the third transmission frame may be less than 2. That is, the priority of the data may be 0 or 1.

Meanwhile, referring to FIG. 7, when the gateway device transmits the first transmission frame in the first transmission period and transmits the third transmission frame in the remaining transmission available time, the remaining transmission available time is the amount required for transmission of the third transmission frame. If it is shorter than the time, it is possible to determine whether to preempt the third transmission frame by comparing the size of the data in the third transmission frame and the second threshold. In this case, the second threshold may be set to at least 120 bytes. This is because the minimum size of the data field in fragment frames that can be configured by frame preemption is 60 bytes, and one Ethernet frame must be divided into at least two fragment frames. As an example, when frame preemption is applied to 120 bytes of data, the data may be transmitted through a first fragment frame and a second fragment frame each containing a data field of 60 bytes, where the first fragment A frame may consist of 90 bytes (7+1+6+6+4+2+60+4), and the second fragment frame may consist of 72 bytes (6+1+1+60+4) . Each fragment frame can be at least 64 bytes in size.

If the size of data in the third transmission frame is greater than or equal to the second threshold, the gateway device performs preemption on the third transmission frame and generates the first fragment frame of the third transmission frame in the remaining transmission function time of the first transmission cycle. may be transmitted, and the second fragment frame of the third transmission frame may be transmitted in the second transmission cycle. At this time, in the transmission section of the second transmission cycle, the second transmission frame is transmitted preferentially over the second fragment frame of the third frame, as shown in FIG. 7, or the second transmission frame of the third frame is transmitted preferentially according to the transmission schedule for the fragment frame. A two-piece frame may be transmitted with priority over the second transmission frame. Here, the second transmission cycle may be a transmission cycle following the first transmission cycle or a transmission cycle at any point after the first transmission cycle.

However, as shown in FIG. 8, if the size of the data in the third transmission frame is less than the second threshold, that is, the size of the data to be transmitted through the third transmission frame is larger than the minimum data size that can be divided through frame preemption. If it is small, the gateway device transmits the fourth transmission frame containing data of a size that can be transmitted in the remaining transmission time among the data whose size is less than the first threshold with priority over the third transmission frame, and transmits the third transmission frame. The frame can be controlled to be transmitted in the next transmission cycle of the current transmission cycle. At this time, in the transmission section of the second transmission period, as shown in FIG. 8, the second transmission frame may be transmitted preferentially over the third transmission frame, or the third transmission frame may be transmitted preferentially over the second transmission frame.

Figure 9 is a diagram showing a method of transmitting a frame by a gateway device according to an embodiment of the present invention.

Referring to FIG. 9, the gateway device can receive an Ethernet frame from an external device (S900). The gateway device may store data in an Ethernet frame received from the external device in an input buffer and increase the count value of the input buffer.

When an Ethernet frame is received from the external device, the gateway device can control the transmission order of the data based on priority information about the data included in the Ethernet frame (S910). For example, the gateway device may monitor the count value of the input buffer and start a data classification task when the count value of the input buffer is greater than 0. At this time, the gateway device may store the data in the corresponding buffer based on the size of the data in the input buffer and the priority of the data. Here, the buffer may include a control buffer, class A buffer, class B buffer, priority queuing (PQ) buffer, and short buffer. Control data can be stored in the control buffer, data with priority corresponding to class A (e.g., audio data) can be stored in the class A buffer, and data corresponding to class B can be stored in the class B buffer. Data having a priority (for example, video data) may be stored, and data having a priority corresponding to PQ (for example, text data) may be stored in the PQ buffer. The priority of data may be the highest for control data and the lowest for PQ data. Data whose priority is less than the set value and whose size is smaller than the first threshold value may be stored in the short buffer. Here, the first threshold may be set based on the average value of the data size (or frame size) at which frame preemption occurs.

The gateway device can determine the transmission order for the data stored in each buffer by performing a data classification task. For example, the gateway device calculates the remaining transmission time in the current transmission cycle and the time required to transmit the current frame (or data), and transmits the current frame if the frame transmission time is shorter than the remaining transmission time. . However, if the transmission time of the current frame is longer than the remaining transmission time, the gateway device can check the status of the short buffer. If data exists in the short buffer and the transmission time of the data stored in the short buffer is shorter than the remaining transmission time, the gateway device stores the data stored in the short buffer in the output buffer and calculates the short buffer's count value (the number of remaining data). ) and frame transmission time can be adjusted.

As an example, the gateway device may transmit the first transmission frame in the current transmission cycle and determine the remaining transmission time. If the time required for transmission of the second transmission frame is shorter than the remaining transmission time, the gateway device transmits the second transmission frame within the current transmission period, and the time required for transmission of the second transmission frame is shorter than the remaining transmission time. If it is longer than the available time, the gateway device may determine whether to preempt the second transmission frame based on the priority of data in the second transmission frame.

As an embodiment, when the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of data in the second transmission frame is greater than or equal to a set value, the gateway device provides free access to the second transmission frame. Emtion can be performed.

As another embodiment, if the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of data in the second transmission frame is less than the set value, the gateway device 3 Transmission frames can be transmitted preferentially. In this case, the priority of the data in the third transmission frame may be less than the set value and the size of the data in the third transmission frame may be less than the first threshold. Here, the first threshold may be set based on the average value of the data size at which preemption occurs. And the priority of the data in the second transmission frame and the priority of the data in the third transmission frame may be the same.

Meanwhile, if the time required for transmission of the third transmission frame is shorter than the remaining transmission time, the gateway device controls the third transmission frame to be transmitted within the current transmission period, and controls the transmission of the third transmission frame. If the required time is longer than the remaining transmission time, it is possible to determine whether to preempt the third transmission frame by comparing the size of data in the third transmission frame with a second threshold. Here, the second threshold may be set to at least 120 bytes. The gateway device performs preemption on the third transmission frame when the size of the data in the third transmission frame is greater than or equal to the second threshold, and when the size of the data in the third transmission frame is less than the second threshold. The third transmission frame can be controlled to be transmitted in the next transmission cycle of the current transmission cycle.

Figure 10 is a diagram showing a process in which a gateway device receives data according to an embodiment of the present invention.

Referring to FIG. 10, when a frame (or signal) is received from the outside, the gateway device can check whether an Ethernet frame is input based on header information of the frame (S1000). When the input of the Ethernet frame is confirmed, the gateway device may store the data included in the Ethernet frame in the input buffer (S1010) and increase the count value of the input buffer (S1020). The gateway device can check the number of data stored in the input buffer based on the count value of the input buffer.

Figure 11 is a diagram showing a process in which a gateway device stores data according to an embodiment of the present invention.

Referring to FIG. 11, the gateway device can monitor the input buffer and check the count value of the input buffer (S1100). If the count value of the input buffer is greater than 0, the gateway device can compare the priority and setting value of each data in the input buffer (S1110). If the priority of the corresponding data is less than the setting value, the gateway device may compare the size of the corresponding data with the first threshold (S1120). If the size of the data is smaller than the first threshold, the gateway device checks whether storage space exists in the short buffer (S1130), and if storage space exists, the gateway device can store the data in the short buffer (S1130). S1140). However, if the priority of the data is greater than the set value, the size of the data is greater than the first threshold, or there is no storage space in the short buffer, the gateway device transfers the data to the corresponding priority. It can be stored in the ranking buffer (S1150). Here, the priority buffer may include a control buffer for storing control data, a class A buffer for storing class A data, a class B buffer for storing class B data, and a PQ buffer for storing PQ data. The short buffer can store data smaller than the average data size at which frame preemption occurs.

Afterwards, the gateway device can increase the count value of the short buffer, calculate and store the time required to transmit the corresponding data (S1160), and decrease the count value of the input buffer (S1170).

Figures 12 and 13 are diagrams showing a process in which a gateway device processes data according to an embodiment of the present invention.

Referring to FIG. 12, a gate that controls output may be connected to each priority buffer (control buffer, class A buffer, class B buffer, and PQ buffer). The gateway device checks whether the gate of the control buffer is open (S1200), and if the gate is open, it can retrieve data from the control buffer and store it in the output buffer (S1240). If the gate of the control buffer is closed, check whether the gate of the class A buffer is open (S1210), and if the gate is open, data can be retrieved from the class A buffer and stored in the output buffer (S1240). If the gate of the class A buffer is closed, check whether the gate of the class B buffer is open (S1220), and if the gate is open, data can be retrieved from the class B buffer and stored in the output buffer (S1240). In the case of the PQ buffer, if the gate is open (S1230), the gateway device can retrieve data from the PQ buffer and determine whether transmission is possible in the remaining transmission time of the current transmission cycle.

Specifically, referring to FIG. 13, the gateway device can calculate the remaining transmission time (remaining transmission time) of the current transmission cycle and the time required to transmit the corresponding data. If the transmission time for the data is shorter than the remaining transmission time (S1300), the gateway device can store the data in the output buffer (S1310). However, if the transmission time for the data is longer than the remaining transmission time, the gateway device may check whether data exists in the short buffer and compare it with the remaining transmission time. If the transmission time of the data stored in the short buffer is shorter than the remaining transmission time (S1320), the gateway device may store the data in the output buffer (S1310) and decrease the count value of the short buffer. However, if the transmission time of the data stored in the short buffer is longer than the remaining transmission time, the gateway device may compare the size of the data with the second threshold. If the size of the data is greater than the second threshold (S1330), the gateway device performs preemption on the frame containing the data (S1340), and if the size of the data is less than the second threshold (S1330) The gateway device may determine that preemption cannot be performed on the corresponding data and determine whether other data in the short buffer can be transmitted within the remaining transmission time. Among the data divided by preemption, remaining data that is not transmitted in the remaining transmission time may be stored again in the PQ buffer or short buffer.

The gateway device can monitor the number of frames stored in the output buffer, and when the input of the frame is confirmed, it can output the frame to the Ethernet port.

Meanwhile, each step included in the transmission method performed by the gateway device according to the above-described embodiment may be implemented as a computer program recorded on a recording medium including instructions for causing a processor to perform these steps.

In addition, each step included in the transmission method performed by the gateway device according to the above-described embodiment may be implemented in a computer-readable recording medium on which a computer program including instructions for allowing a processor to perform these steps is recorded. there is.

Combinations of each step in each flowchart attached to the present invention may be performed by computer program instructions. Since these computer program instructions can be mounted on the processor of a general-purpose computer, special-purpose computer, or other programmable data processing equipment, the instructions performed through the processor of the computer or other programmable data processing equipment perform the functions described in each step of the flow chart. It creates the means to carry out these tasks. These computer program instructions may also be stored on a computer-usable or computer-readable recording medium that can be directed to a computer or other programmable data processing equipment to implement a function in a particular way, so that the computer program instructions are computer-usable or computer-readable. The instructions stored in the recording medium can also produce manufactured items containing instruction means that perform the functions described in each step of the flowchart. Computer program instructions can also be mounted on a computer or other programmable data processing equipment, so that a series of operational steps are performed on the computer or other programmable data processing equipment to create a process that is executed by the computer, thereby generating a process that is executed by the computer or other programmable data processing equipment. Instructions that perform processing equipment may also provide steps for executing the functions described in each step of the flowchart.

Additionally, each step may represent a module, segment, or portion of code containing one or more executable instructions for executing specified logical function(s). Additionally, it should be noted that in some alternative embodiments it is possible for the functions mentioned in the steps to occur out of order. For example, two steps shown in succession may in fact be performed substantially simultaneously, or the steps may sometimes be performed in reverse order depending on the corresponding function.

The above description is merely an illustrative explanation of the technical idea of the present invention, and those skilled in the art will be able to make various modifications and variations without departing from the essential quality of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention shall be interpreted in accordance with the claims below, and all technical ideas within the scope equivalent thereto shall be construed as being included in the scope of rights of the present invention.

100: gateway device
110: input unit
120: control unit
130: output unit
210: first ECU
220: 2nd ECU
230: 3rd ECU

Claims (20)

In the gateway device,
An input unit configured to receive an Ethernet frame;
a control unit configured to control the transmission order of the data based on priority information about the data included in the Ethernet frame; and
An output unit configured to output a first transmission frame based on the transmission order,
The control unit,
If the time required to transmit the second transmission frame is shorter than the remaining transmission time remaining after transmitting the first transmission frame in the current transmission cycle, control the second transmission frame to be transmitted within the current transmission cycle,
When the time required for transmission of the second transmission frame is longer than the remaining transmission time, determining whether to preempt the second transmission frame based on the priority of data in the second transmission frame Featured device. According to paragraph 1,
The control unit,
When the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of data in the second transmission frame is greater than a set value, the preemption is performed on the second transmission frame. A device that does. According to paragraph 1,
The control unit,
If the time required to transmit the second transmission frame is longer than the remaining transmission time and the priority of the data in the second transmission frame is less than the set value, the priority of the data in the third transmission frame is less than the set value, and A device characterized in that the third transmission frame is controlled to be transmitted preferentially over the second transmission frame based on the size of the data in the third transmission frame being less than a first threshold. According to paragraph 3,
The first threshold is,
A device wherein the preemption is set based on an average value of the data size generated. According to paragraph 3,
A device characterized in that the priority of the data in the second transmission frame and the priority of the data in the third transmission frame are the same. According to paragraph 3,
The control unit,
If the time required to transmit the third transmission frame is shorter than the remaining transmission time, control the third transmission frame to be transmitted within the current transmission period,
When the time required for transmission of the third transmission frame is longer than the remaining transmission time, the size of the data in the third transmission frame is compared with a second threshold to determine whether to preempt the third transmission frame. A device characterized in that. According to clause 6,
The second threshold is,
A device characterized in that it is set to at least 120 bytes. According to clause 6,
The control unit,
Performing the preemption on the third transmission frame based on the size of the data in the third transmission frame being greater than or equal to the second threshold,
A device characterized in that controlling the third transmission frame to be transmitted in a transmission cycle after the current transmission cycle based on the size of the data in the third transmission frame being less than the second threshold. In a transmission method by a gateway device,
Step of receiving an Ethernet frame;
Controlling the transmission order of the data based on priority information about the data included in the Ethernet frame; and
Including outputting a first transmission frame based on the transmission order,
If the time required to transmit the second transmission frame is shorter than the remaining transmission time remaining after transmitting the first transmission frame in the current transmission cycle, the second transmission frame is transmitted within the current transmission cycle,
When the time required for transmission of the second transmission frame is longer than the remaining transmission time, whether to preempt the second transmission frame is determined based on the priority of data in the second transmission frame. How to feature. According to clause 9,
When the time required for transmission of the second transmission frame is longer than the remaining transmission time and the priority of data in the second transmission frame is greater than a set value, the preemption is performed on the second transmission frame. How to. According to clause 9,
If the time required to transmit the second transmission frame is longer than the remaining transmission time and the priority of the data in the second transmission frame is less than the set value, the priority of the data in the third transmission frame is less than the set value, and A method wherein the third transmission frame is transmitted preferentially over the second transmission frame based on the size of the data in the third transmission frame being less than a first threshold. According to clause 11,
The first threshold is,
A method characterized in that the preemption is set based on the average value of the generated data size. According to clause 11,
A method wherein the priority of the data in the second transmission frame and the priority of the data in the third transmission frame are the same. According to clause 11,
If the time required for transmission of the third transmission frame is shorter than the remaining transmission time, the third transmission frame is transmitted within the current transmission period,
When the time required for transmission of the third transmission frame is longer than the remaining transmission time, whether to preempt the third transmission frame is determined by comparing the size of the data in the third transmission frame and the second threshold. A method characterized by: According to clause 14,
The second threshold is,
A method characterized in that it is set to at least 120 bytes. According to clause 14,
The preemption is performed on the third transmission frame based on the size of the data in the third transmission frame being greater than or equal to the second threshold,
The method characterized in that the third transmission frame is transmitted in a transmission cycle after the current transmission cycle based on the size of the data in the third transmission frame being less than the second threshold. In the gateway device,
An input unit configured to receive an Ethernet frame;
A control unit configured to store the data in a corresponding buffer among a plurality of buffers based on at least one of priority information and length information for data included in the Ethernet frame and to control the transmission order of data in the plurality of buffers. ; and
An output unit configured to output a first transmission frame based on the transmission order,
The control unit,
If the time required to transmit the second transmission frame including data stored in the first buffer among the plurality of buffers is shorter than the remaining transmission time remaining after transmitting the first transmission frame in the current transmission cycle, the second transmission frame Control to transmit within the current transmission cycle,
If the time required to transmit the second transmission frame is longer than the remaining transmission time, whether to preempt the second transmission frame is determined based on the size of data in the second buffer among the plurality of buffers. A device characterized in that. In a transmission method by a gateway device,
Step of receiving an Ethernet frame;
storing the data in a corresponding buffer among a plurality of buffers based on priority information about data included in the Ethernet frame;
Controlling the transmission order of data in the plurality of buffers; and
Including outputting a first transmission frame based on the transmission order,
If the time required to transmit the second transmission frame including data stored in the first buffer among the plurality of buffers is shorter than the remaining transmission time remaining after transmitting the first transmission frame in the current transmission cycle, the second transmission frame is transmitted within the current transmission cycle,
If the time required to transmit the second transmission frame is longer than the remaining transmission time, whether to preempt the second transmission frame is determined based on the size of data in the second buffer among the plurality of buffers. A method characterized by being. A computer program stored on a computer-readable recording medium,
When the computer program is executed by a processor,
A step of receiving an Ethernet frame,
controlling the transmission order of the data based on priority information about the data included in the Ethernet frame;
Includes instructions for causing the processor to perform a transmission method of outputting a first transmission frame based on the transmission order,
If the time required to transmit the second transmission frame is shorter than the remaining transmission time remaining after transmitting the first transmission frame in the current transmission cycle, the second transmission frame is transmitted within the current transmission cycle,
When the time required for transmission of the second transmission frame is longer than the remaining transmission time, whether to preempt the second transmission frame is determined based on the priority of data in the second transmission frame. A computer program characterized by A computer-readable recording medium storing a computer program,
When the computer program is executed by a processor,
A step of receiving an Ethernet frame,
controlling the transmission order of the data based on priority information about the data included in the Ethernet frame;
Includes instructions for causing the processor to perform a transmission method of outputting a first transmission frame based on the transmission order,
If the time required to transmit the second transmission frame is shorter than the remaining transmission time remaining after transmitting the first transmission frame in the current transmission cycle, the second transmission frame is transmitted within the current transmission cycle,
When the time required for transmission of the second transmission frame is longer than the remaining transmission time, whether to preempt the second transmission frame is determined based on the priority of data in the second transmission frame. A computer-readable recording medium characterized by:

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